This invention relates to computer input devices. Particular embodiments provide pointing devices which can be used both as a mouse and as a trackball.
Various known pointing devices allow a user to provide two-dimensional coordinate information to a computer. One such device is a mouse. A typical mouse has a spherical ball mounted in a housing. The ball projects slightly from a bottom side of the housing. A user can cause the ball to rotate by sliding the mouse over a flat surface. Sensors in the mouse sense rotation of the spherical ball about two orthogonal axes. Signals output by the sensors are delivered to a computer. The signals may be interpreted by software in the computer to determine a location of a cursor in two dimensions on a display of the computer. One or more function buttons are provided on the housing in position(s) where they can be easily actuated by a user grasping the mouse. By pushing the buttons a user can generate additional signals to be sent to the computer.
Mice are very popular because they provide users with an intuitive way to provide input to a computer. A mouse can provide fine control over cursor position in two dimensions. Some mice are equipped with wheels. The wheels are located on an upper surface of the mouse. A user can use a wheel equipped mouse (together with suitable software drivers) for scrolling through lists of items. One disadvantage of a mouse is that a mouse requires the availability of a flat surface for proper operation. This can be a problem, for example, when a mouse is used as a pointing device for a portable laptop computer and the computer is being used in a location where there is no convenient flat surface.
An alternative type of pointing device is a trackball. A trackball has a spherical ball mounted in and projecting upwardly from a housing. A user can roll the spherical ball by directly manipulating it. Trackballs have the advantages that they do not require a large flat surface for proper operation and the location of a trackball does not change as the trackball is used.
Over the past number of years considerable research has been conducted into the ergonomics of computer input devices. These enquiries have been prompted by the discovery that people who use computers for long periods of time can suffer various injuries including so-called xe2x80x9crepetitive strain injuriesxe2x80x9d. Repetitive strain injuries can occur when users repetitively make thousands of very similar motions of the same muscles over a long period. Furthermore, even if a user does not suffer physical injury, the user can become fatigued after using a mouse or trackball to control a computer for extended periods. This can lead to reduced productivity.
The combinations of hand and arm muscles used to control a mouse are different from the combination of hand and finger muscles used to control a trackball. A computer user may reduce the risk of repetitive strain injuries and also reduce fatigue by periodically switching between a mouse and a trackball. When using a mouse the muscles used to control a trackball can rest and vice versa.
Various designs have been proposed for computer pointing devices which can be operated selectively either as mice or as trackballs. All of these prior devices have significant disadvantages. Jasinski et al., U.S. Pat. No. 5,063,289 discloses a combined mouse and trackball. The grip portion of the device, which is gripped when the device is being used as a mouse, serves as a base when the device is being used as a trackball. The grip portion cannot therefore be ergonomically shaped. Further, the Janiski et al. design requires two separate sets of function buttons. When the Janiski et al. device is used as a trackball the function buttons are not ergonomically positioned. The way in which the device converts to a mouse prevents a more optimum location for the trackball function buttons. Overall, this design forces the user to adopt an awkward hand posture to operate the device.
Blankenship et al., U.S. Pat. No. 5,726,684 shows another combination mouse and trackball device. The Blankenship device can be built into the keyboard of a laptop computer. The device can be used in place as a trackball. The device can be removed from the keyboard and turned upside down for use as a mouse. The Blankenship design also requires two different sets of function buttons and has the further disadvantages that the grip portion of the device is not ergonomically shaped. Further, the trackball function buttons are not optimally located.
Kwok, U.S. Pat. No. 5,280,726 shows a combination mouse and trackball. The ball can be moved between a lower position wherein the device functions as a mouse and an upper position wherein the ball can be manipulated as a trackball by an elevator mechanism. The Kwok device has the disadvantage that the buttons are located in a position which is convenient when the device is being used as a mouse but is awkward when the device is being used as a trackball.
Hovey et al., U.S. Pat. No. 4,562,347 shows another combination mouse and trackball device. The Hovey et al. device has a large ball which projects from both upper and lower faces of a housing. Because the ball projects upwardly from the housing, a user""s hand could unintentionally interfere with rotation of the ball when the device is being used as a mouse. To use the device as a trackball a user must support the housing so that the ball is clear of any surfaces and can freely rotate. Furthermore, when this device is used as a trackball, the function buttons are located in positions which require a user to adopt an awkward hand posture when using the device.
Grant, U.S. design Pat. Nos. D361,991 and D346,373, both entitled xe2x80x9cCombined Trackball and Mousexe2x80x9d show devices in which a trackball projects from a front surface of a housing and a mouse ball projects from a lower surface of the housing. It appears that the same ball serves as both as a mouse ball and a trackball.
There is a need for a computer pointing device which can be operated both as a mouse which has the ease of operation of a well designed mouse and as a trackball which has the ease of operation of a well designed trackball. There is a particular need for such a device which provides a mouse having an ergonomically shaped grip. There is also a particular need for computer input devices which can be adjusted to comfortably accommodate hands of different sizes. Especially in mobile computing there is a need for computer input devices which can be configured in a way which protects position sensors, such as balls, and other sensitive movable parts, from dirt and physical damage while they are not being used. In some computing environments, there is also a need for input devices which can be configured to allow a user to operate the devices with two hands.
This invention provides computer input devices which can function as computer mice. A mouse has a position sensor, which typically comprises a rolling ball. When an operator moves the mouse relative to a flat surface the position sensor generates signals which can be used by a host computer. The host computer may, for example, use the signals to position a cursor on a screen. A mouse also has one or more function buttons which a user can press to send control signals to a host computer. The input devices of the invention have function buttons and position sensors which can be moved relative to one another. In various embodiments this permits an input device according to the invention to
be used selectively as a mouse or as a trackball;
be adjusted to fit different hand sizes;
be placed in a xe2x80x9cstoragexe2x80x9d configuration wherein the position sensor is protected from damage and dirt; or,
be used for two-handed input control, with the function button located for convenient operation by one hand of a user and the position sensor operable by the other hand of the user.
Accordingly, one aspect of the invention provides a computer input device comprising a function-button-carrying member; at least one function button on the function-button-carrying member; a position sensor-carrying member which is moveably coupled to the function-button-carrying member; and, a position sensor on the position sensor-carrying member. When the position sensor-carrying member is in a first position relative to the function-button-carrying member, the input device is operable as a mouse.
In various specific embodiments of the invention the ball-carrying member is connected in different ways to the function-button-carrying member to allow the ball-carrying member to be moved between its two positions. In one embodiment of the invention the ball-carrying member is slidably coupled to the function-button-carrying member. In another embodiment of the invention the ball-carrying member is pivotally coupled to the function-button-carrying member. The ball-carrying member may be pivotally coupled to the function button-carrying member for relative movement about a generally vertical axis or about a generally horizontal axis.
In one preferred embodiment, the position sensor comprises a rotatable ball and, when the position sensor-carrying member is in a second position relative to the function-button-carrying member, an upper surface of the ball is exposed so that the input device is usable as a trackball. Preferably, with the position sensor-carrying member in the second position the user can rest the palm of one hand on a surface of the function-button-carrying member, operate the function button with the forefinger of the hand, and roll the rotatable ball with the thumb of the hand.
In another preferred embodiment, when the position sensor-carrying member is in a storage position relative to the function-button-carrying member, the position sensor is enclosed and protected by the position sensor-carrying member and the function-button-carrying member. This is particularly useful in mobile computing.
In yet another preferred embodiment a dimension of a hand-grippable portion of the input device, or a distance between the position sensor and other parts of the device is adjustable by moving the position sensor-carrying member relative to the function-button-carrying member. This permits the computer input device to be adapted for use by hands of different sizes.
In still another preferred embodiment, the position sensor-carrying member can be moved into a position relative to the function-button-carrying member wherein a user can operate the function button with one hand and can operate the position sensor with another hand. This permits the user to use the computer input device for two handed input control.
A second aspect of the invention provides computer input device which is selectively operable as a mouse or as a trackball. The input device comprises a function-button-carrying member; at least one function button on a face of the function-button-carrying member; a position sensor-carrying member moveably coupled to the function-button-carrying member; and, a position sensor on the position sensor-carrying member and moveable therewith relative to the function-button-carrying member. The position sensor-carrying member has a first position, wherein the position sensor is located beneath the face of the function-button-carrying member and the position sensor is oriented to detect relative motion between the input device and a surface beneath the input device so that the input device is usable as a mouse. The position sensor-carrying member is movable from the first position to a second position, wherein the position sensor-carrying member is displaced relative to the function button-carrying member and the position sensor is oriented to detect relative motion between the position sensor and a user""s hand.
In a preferred embodiment, the position sensor comprises a ball supported for rotation on the position sensor-carrying member and a sensor associated with the ball. The sensor generates a signal describing rotation of the ball. When the position sensor carrying member is in its first position, the ball can be frictionally engaged with a surface under the input device and when the position sensor carrying member is in its second position the ball can be manually rotated to permit the input device to be used as a trackball. The position sensor-carrying member is slidably coupled to the function-button-carrying member in some particular embodiments and is pivotally coupled to the function-button-carrying member in other particular embodiments.
Another aspect of the invention provides a computer input device comprising: a function-button-carrying member; at least one function button on a face of the function-button-carrying member; a position sensor-carrying member detachably coupled to the function-button-carrying member; and, a position sensor on the position sensor-carrying member. The position sensor-carrying member may be coupled to the function-button-carrying member in a first position in which the position sensor is positioned beneath the function button-carrying member where it can detect motion of the input device relative to a surface beneath the input device to permit the input device to be used as a mouse. When the position sensor-carrying member is separated from the function button-carrying member the position sensor carrying member can be located a sufficient distance from the function-button carrying member to permit two-handed operation of the input device.
A still further aspect of the invention provides a computer input device comprising a position sensor-carrying member; a position sensor on the position sensor-carrying member and function-button-carrying member. The function-button-carrying member is configured to receive the position sensor carrying member in each of: a first position wherein the position sensor is exposed and the device is usable as a mouse; and, a second position wherein the position sensor is enclosed by the position sensor-carrying member and the function-button-carrying member.
Further features and advantages of the invention are set out below.